Glioblastomas (GBMs) account for almost half of all cancerous brain tumors in adults. This brain cancer grows rapidly and can spread throughout the brain. New treatments, including tumor treatment fields and targeted therapies, help ease symptoms and slow cancer growth.
Glioblastoma multiforme (GBM) is the most common type of malignant (cancerous) brain tumor in adults. Cancer cells in GBM tumors rapidly multiply. The cancer can spread into other areas of the brain as well. Rarely, the cancer spreads outside the brain to other parts of the body.
Glioma tumors like GBM start in glial cells. Glial cells are vital to nerve cell function. GBMs specifically form in glial cells called astrocytes. GBMs are the fastest-growing astrocytoma (tumor that forms in astrocytes).
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More than 13,000 Americans are diagnosed with GBM every year. GBM accounts for almost half of all cancerous brain tumors.
GBM commonly affects people age 45 to 70. The average age at diagnosis is 64. Men have a slightly higher risk, but the disease affects all ages and genders.
These factors may increase your risk:
Experts don’t know why some people develop cancerous brain tumors, including GBM.
GBM symptoms tend to come on quickly. The growing tumor puts pressure on the brain, causing:
If your healthcare provider suspects a brain tumor, you may get these tests:
Healthcare providers use a grading system from 1 to 4 to indicate brain tumor growth. Grade 1 brain tumors grow slowly and are the least aggressive. Grade 4 tumors grow rapidly and are more aggressive.
GBMs are grade 4 by definition. GBM can be either primary or secondary. Primary GBM develops directly from glial cells. On the contrary, occasionally grade 1 glial tumors can progress to become GBMs; this is called secondary GBM.
GBM and its treatments can affect brain function. You may experience mood changes and memory problems. Most people with GBM eventually have to stop working and driving. You may need full-time care. These changes may make you feel anxious or depressed.
Unfortunately, there isn’t a cure for GBM. Treatments focus on removing or shrinking the tumor to reduce symptoms.
The first step is surgery to remove the tumor (craniotomy), followed by radiation and chemotherapy. If surgery isn’t an option due to your health or the tumor location, radiation and chemotherapy can control the tumor.
GBM treatments include:
GBM is aggressive cancer that is difficult to treat. There isn’t a cure. Treatments ease symptoms and help you stay comfortable and prolong your life. There are many clinical trials underway to find new GBM treatments.
Therapies that target specific cancer cell genes show promise. Researchers are also looking at ways to deliver chemotherapy directly to the brain tumor. Your healthcare provider can determine whether a clinical trial is right for you.
Unfortunately, most people live on average 12 to 18 months after diagnosis. Only about 7% of people are still alive in five years.
You should call your healthcare provider if you experience:
You may want to ask your healthcare provider:
A note from Cleveland Clinic
Finding out you have GBM can be difficult. The disease grows quickly and treatment is challenging. Researchers continue to look for new ways to treat GBM. For now, treatments can minimize symptoms and improve your quality of life. Talk to your healthcare provider about treatment options, including clinical trials.
Last reviewed by a Cleveland Clinic medical professional on 09/03/2021.
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